It depends on how many balls that you are carrying, if you are carrying 6 upwards i think that there is enough of a difference.  But less than that i think it is hard to justify.

The Action for me has similar shape to the big bully, but it is a bit more of everything.  So when you play on heavier patterns expect to see that similar smooth reaction that you got from the Big Bully on the medium patterns

This is my take on the 2 balls anyways, any other opinions??